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Women's Health Guide

PMOS

Formerly known as PCOS - what the new name means for you

1 in 8
women are affected - making it one of the most common hormonal conditions globally
⚠
Medical disclaimer

This page provides general health information. It is not a substitute for personalised medical advice, diagnosis, or treatment. Every person's situation is different. If you have concerns about your health, please speak to your GP or a qualified healthcare professional.

If you have been diagnosed with PCOS - or have been researching it - you may have recently heard that the name has changed. In May 2026, a landmark paper published in The Lancet by Teede et al. and the Global Name Change Consortium announced that polycystic ovary syndrome (PCOS) has been officially renamed polyendocrine metabolic ovarian syndrome, or PMOS. The name change followed an unprecedented global consensus process involving 56 leading academic, clinical and patient organisations, and surveys of over 14,000 people living with the condition.

The old name was always misleading - it implied pathological ovarian cysts, when in fact the 'cysts' are small underdeveloped follicles, and cysts are not the defining feature of the condition at all. PMOS better reflects what the condition actually is: a multisystem condition involving endocrine (hormonal), metabolic, and ovarian dysfunction. Everything else about the condition - the diagnosis, the symptoms, the management - remains the same. The name is new; the condition and its treatments are not.

This page uses the new name PMOS throughout, with PCOS noted for those who may still be searching under the old term.

Symptoms to know

Irregular or absent periods (oligomenorrhoea or amenorrhoea)
Cycles longer than 35 days, unpredictable, or absent. This occurs because follicles do not develop properly, so ovulation is irregular or absent. This is one of the three Rotterdam diagnostic criteria.
Excess hair growth (hirsutism)
Hair growth on the face, chest, back or abdomen due to elevated androgens. This is one of the most distressing symptoms for many women and is a clinical marker of hyperandrogenism - one of the Rotterdam criteria.
Acne or oily skin
Particularly hormonal acne that flares cyclically, often on the jaw, chin and neck. Androgen-related acne in adults often does not respond to typical skincare and may require hormonal management.
Thinning hair on the scalp (androgenic alopecia)
Thinning or shedding in a male-pattern distribution. Elevated androgens are typically the driver. Worth mentioning to your GP or gynaecologist.
Weight gain or difficulty managing weight
Particularly around the abdomen. Insulin resistance, present in a significant proportion of women with PMOS, makes the body store fat more readily and makes weight management genuinely harder.
Mood changes
PMOS is associated with higher rates of anxiety and depression. This is not purely a psychological response to having a difficult condition - there appears to be a direct hormonal and metabolic link.
Difficulty conceiving
Irregular or absent ovulation means conception can take longer. PMOS is one of the most common causes of ovulatory infertility, but is also one of the most treatable.

What actually helps

Get the right investigations
A PMOS workup should include blood tests (LH, FSH, total and free testosterone, SHBG, prolactin, thyroid function, fasting glucose or HbA1c) and a pelvic ultrasound. NICE guidelines sets out what investigations should be offered. If you have only been told you have PMOS or PCOS based on a scan alone, ask for bloodwork.
Address insulin resistance if present
Insulin resistance is often the driver of many PMOS symptoms. Dietary changes that reduce blood glucose spikes - lower refined carbohydrate intake, more fibre, regular meals - are supported by evidence. Lifestyle intervention is recommended as first-line management. Metformin is also effective for insulin resistance in PMOS and is recommended in NICE guidelines where lifestyle measures are insufficient.
Consider myo-inositol
Myo-inositol (often combined with D-chiro-inositol in a 40:1 ratio) has a growing evidence base for improving insulin sensitivity, cycle regularity and ovulatory function in PMOS. It is available over the counter and has a good safety profile. It is not a replacement for medical management, but for many women it is a useful adjunct.
Move regularly - regardless of weight change
Exercise, particularly resistance training and moderate cardiovascular activity, improves insulin sensitivity and supports hormonal balance in PMOS. Aim for at least 150 minutes of moderate activity or 75 minutes of vigorous activity per week. The benefits on hormonal health exist independently of any change in body weight.
Know your options for cycle regulation
If you are not trying to conceive, the combined contraceptive pill can regulate cycles and reduce androgen-related symptoms (acne, hirsutism). If you are trying to conceive, letrozole is the recommended first-line ovulation induction agent, having superseded clomifene as the preferred option in most guidelines. These should be prescribed under specialist supervision.
Do not accept 'just lose weight' as a plan
Weight management may be appropriate for some women with PMOS, but it is not the only treatment, not appropriate for every patient, and should never be delivered as a dismissal. If you leave an appointment feeling unheard or without a clear plan, seek a second opinion from a gynaecologist with endocrine expertise.

Myths worth busting

Myth
“PMOS means you have cysts on your ovaries”
This is precisely why the name was changed. The condition involves small, underdeveloped follicles - not pathological cysts. The old name (PCOS) was inaccurate and contributed to widespread confusion. The Lancet 2026 name change paper specifically cites this as a key reason for renaming.
Myth
“You cannot have PMOS if your periods are regular”
PMOS has different phenotypes (presentations). The Rotterdam criteria allow diagnosis with only 2 of the 3 features: irregular ovulation, elevated androgens, and polycystic ovaries on scan. You can have elevated androgens and polycystic ovaries with regular cycles - this is sometimes called a 'non-classic' phenotype.
Myth
“PMOS means you cannot get pregnant”
PMOS is one of the most treatable causes of infertility. With appropriate management - from lifestyle measures to ovulation induction - the majority of women with PMOS who wish to conceive are able to do so.
Myth
“The pill treats PMOS”
The combined contraceptive pill manages symptoms of PMOS - cycle regulation, acne, hirsutism - but it does not treat the underlying hormonal imbalance. When you stop it, PMOS is still there. This is not a reason not to use it, but you should understand what it is and is not doing.

Frequently asked questions

Why has PCOS been renamed PMOS?
In May 2026, a global consensus process involving 56 leading organisations and over 14,000 people with the condition concluded that the name 'polycystic ovary syndrome' was scientifically inaccurate and misleading. It implied pathological ovarian cysts (which are not a feature of the condition), obscured its true endocrine and metabolic nature, and contributed to delayed diagnosis and stigma. The new name - polyendocrine metabolic ovarian syndrome (PMOS) - better reflects the multisystem nature of the condition. The diagnosis criteria and management have not changed.
What are the symptoms of PMOS (formerly PCOS)?
The main symptoms are irregular or absent periods, excess hair growth on the face and body (hirsutism), acne or oily skin, thinning hair on the scalp, difficulty managing weight (particularly around the abdomen), mood changes, and difficulty conceiving. Not everyone has all of these - PMOS presents differently in different people. NICE guidelines sets out the full clinical picture.
How is PMOS diagnosed?
PMOS is still diagnosed using the Rotterdam criteria: at least 2 of the following 3 features are needed - irregular or absent ovulation, elevated androgens (on blood test or clinically as hirsutism/acne), and polycystic ovaries on ultrasound. Blood tests and a scan are both important. The name has changed; the diagnostic process has not.
Can you have PMOS without irregular periods?
Yes. PMOS has different phenotypes. The Rotterdam criteria allow diagnosis with only 2 of the 3 features: irregular ovulation, elevated androgens, and polycystic ovaries on scan. You can have elevated androgens and polycystic ovaries with regular cycles. Symptoms like acne, hirsutism and difficulty conceiving can still be present.
What is the best diet for PMOS?
There is no single 'PMOS diet'. The evidence supports a healthy diet consistent with public health guidelines - emphasising whole grains, vegetables, lean proteins and healthy fats, with the primary goal of supporting insulin sensitivity. A Mediterranean-style dietary pattern has the most evidence in this context. Reducing refined carbohydrates and ultra-processed foods is generally well-supported. Be sceptical of any branded 'PCOS' or 'PMOS' diet plans.
Is PMOS linked to diabetes?
Yes. Insulin resistance is a core feature of PMOS and increases the long-term risk of type 2 diabetes. NICE guidelines recommends regular monitoring of fasting glucose or HbA1c for women with the condition. Lifestyle intervention and, where appropriate, metformin can significantly reduce this risk. This is a reason to stay engaged with management long term, not just around fertility.
Is PMOS a lifelong condition?
PMOS is a lifelong condition, though symptoms change over time. The reproductive features (irregular periods, ovulatory dysfunction) resolve after menopause. The metabolic features - insulin resistance, cardiovascular risk - persist and should continue to be monitored. With the right long-term management plan, most women with PMOS manage their symptoms well.

Sources & references

All clinical claims on this page are grounded in current evidence and published guidelines. Links open external websites.

  1. Teede HJ et al. Polyendocrine metabolic ovarian syndrome, the new name for PCOS: a multistep global consensus process. The Lancet, 2026
  2. NICE CKS: Polycystic ovary syndrome (guidance current pending update to reflect name change)
  3. WHO: Polycystic ovary syndrome
  4. NHS: Polycystic ovary syndrome (PCOS)

Last reviewed: July 2026. This page will be updated as guidelines change. If you spot an error or an outdated reference, please get in touch.

Dr Hiba Sher Khan
© 2026 Dr Hiba Sher Khan · drhiba.co.uk